Sub-triangle of A008292: take every second term of every second row.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =66a(5) =1a(6) =1a(7) =1191a(8) =1191a(9) =1a(10) =1a(11) =14608a(12) =156190a(13) =14608a(14) =1a(15) =1a(16) =152637a(17) =9738114a(18) =9738114a(19) =152637a(20) =1a(21) =1a(22) =1479726a(23) =423281535a(24) =2275172004a(25) =423281535a(26) =1479726a(27) =1a(28) =1a(29) =13824739